To be honest, whether the food I buy is "sustainable" or not isn't a major concern to me.
Heresy, I know.
That's not to say that I don't do my part to save the environment and support my local food producers -- I don't own a car, I receive a weekly farm share, I once found myself discussing the topic of men's a cappella music in an extended conversation with Ralph Nader -- but, when it comes down to it, I'll take delicious over eco-friendly any day of the week. Stone me if you must.
That being said, a great deal of both local and/or sustainable food is delicious; to suggest otherwise would be more than foolish. As far as I'm concerned, as long I can get great flavor along with the smug self-satisfaction that comes with paying seven dollars for a handful of asparagus, well then, by golly, I'm on board.

